https://doi.org/10.1140/epja/i2012-12186-2
Regular Article - Experimental Physics
Revisiting the decay scheme and half-life of 139Ba
1
Nuclear Physics Division, Bhabha Atomic Research Centre, 400085, Mumbai, India
2
Homi Bhabha Centre for Science Education, 400085, Mumbai, India
3
Radiochemistry Division, Bhabha Atomic Research Centre, 400085, Mumbai, India
4
Department of Physics and Astronomy, McMaster University, L8S 4M1, Ontario, Canada
* e-mail: pkjoshi@tifr.res.in
Received:
3
July
2012
Revised:
22
October
2012
Accepted:
26
October
2012
Published online:
17
December
2012
The decay of 139Ba to levels of 139La has been studied employing singles and 
- coincidence spectroscopy techniques, using four Compton suppressed Clover detectors. The - coincidence data obtained in the present work has been more conclusive as compared to the coincidence data obtained using NaI(Tl)-Ge(Li) detectors in the earlier investigations. The relative intensities of twenty-seven -ray transitions have been determined. The -ray transitions with energies 1044 and 1525keV, attributed to the decay of 139Ba in the previous works, have been found to be due to long-lived impurities. The 1691keV transition, previously assigned to the decay of 139Ba , is found to be mainly associated with an impurity with only a small fraction belonging to 139Ba decay. The half-life of 139Ba has been measured. The present work attempts to resolve some of the discrepancies in the previous investigations, which will be helpful in the precise determination of 
-decay scheme of 139Ba.
© SIF, Springer-Verlag Berlin Heidelberg, 2012
